In general, multiterminal integrated circuit (IC) packages are formed from a copper leadframe. FIG. 1A shows such a prior art process. A bare copper leadframe 100 shown in a top view and a bottom view is partially etched to pattern the contact leads 120 and the die attach pad 110. The partial etching is able to be done in any number of ways known by the person of ordinary skill. The contact leads 120 are generally etched to a partial thickness portion 122 and a full thickness portion 121. As used herein, the term “full thickness” generally denotes a member or structure being the same thickness as the original monolithic metal substrate from which the structure is etched. “Partial thickness” generally denotes that the structure has been etched to a partially, so the thickness is some fraction of the thickness of the original substrate. The full thickness portion 121 is such that the bottom surface 123 is exposed when the leadframe 100 is eventually encased in a mold compound. The exposed area of the full thickness portion 121 is soldered into application, such as a PC board having several traces and contact pads for forming an electrical connection with a semiconductor die (not shown) housed within the IC package. The partial thickness portion 122 extends away from the die attach pad 110. A plated portion 124 at the end of the contact lead 120 closest to the die attach pad 110, or the proximal end, receives a wire bond (not shown) for forming an electrical connection with a semiconductor die. As a result, an electrical connection is formed between the semiconductor die and the bottom surface 123 of the contact lead 120.
FIG. 1B shows a cross section of the copper leadframe 100 and the contact leads 120. A semiconductor die 111 is mounted on a top surface of the die attach pad 110. Bond wires 142 are mounted from the semiconductor die 111 to the partial thickness portion 122 of the contact lead 120. However, as shown in FIG. 1C, because of the flexible nature of most metals including copper, the partial thickness portion 122 bends when a capillary 140 attempts to place the bond wire 142 onto the plated end 124. Therefore, as shown in FIG. 1D, the partial thickness portion 122 rebounds and may cause the bond wire 142 to lift before a proper weld can be established. As a result, the entire device is generally scrapped, as the time-cost of repair can outweigh the cost of a new unit. Furthermore, as shown in FIG. 1E, the partial thickness portions 122′ can easily become bent or destroyed due to improper handling. Again, the leadframe 100 with the bent contact leads 120′ is scrapped. Such scrap adversely affects manufacturing yield. It is well known that the semiconductor industry is highly cost driven, and any phenomenon that causes lower than optimum yield causes manufacturing costs to increase. To that end, it is highly desirable to optimize manufacturing yield.